Sale Sharks flanker Hendre Fourie looks set for another spell on the sidelines after injuring his shoulder against Worcester Warriors.
The South African-born back-rower went off after 14 minutes in their 15-12 Aviva Premiership victory over the Warriors.
Fourie had been out of action for five months with similar issues and returned impressively last week, producing a man-of-the-match display against the Scarlets.
However, head coach Tony Hanks admitted the back-rower was fuming after coming off injured.
"I know he's a pretty angry man at the moment, he's very frustrated," Hanks said.
"It's the other arm and I think it's in a [ice] pack at the moment.
"We'll have a look at him tomorrow. My medical prognosis is not the one you want, but we'll have a look at him tomorrow and assess him.
"Most of these things normally take a couple of days before they get scanned. It's a real shame because Hendre's worked so hard, he was outstanding for us last week.
"We couldn't pick between him and Dave Seymour so we decided to put both out there and we were really looking forward to them both having a crack. Hopefully, it's not too long so we can get him out there soon."
On a more positive note for the Sharks, prop Andrew Sheridan returned for the first time since England's World Cup game against Argentina, and Hanks was delighted with his impact.
"It's the first time I've been able to coach Sherry and I was really looking forward to it," he said.
"To get him through 80 minutes, finishing the game with Tony Buckley at lock and Sherry out there [was important]."
By contrast, Hanks' opposite number Richard Hill was frustrated with some of the refereeing at the scrum.
Despite appearing to have the upper hand, the Worcester head coach thought Llyr Ap Geraint Roberts was harsh on his side at the set-piece.
"Particularly early on, there were a couple of scrum decisions which I didn't personally agree with," Hill said.
"The first two scrums were very disappointing, but after that it seemed to right itself and the referee seemed to realise that we were on top in the scrums and gave us the advantage.
"You see scrums refereed every week, it's a hard old job. We were five penalties against in the first 10 minutes and I thought, 'this is not going to go well at all', but it did even itself later on.
"I know referees are very reluctant, unless it's a stonewall penalty, they're reluctant to give a penalty in the last play of the game."
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